Gear finishing machine



8, 1951 w. s. PRAEG ET AL GEAR FINISHING MACHINE 4 Sheets-Sheet 1 Filed Jan. 19, 1948 I Ill! ||||1\| INVENTORS WALTER s. PRAEG y ARTHUR B. BASSOFF 9 M ATTORNEYS Aug. 28, 1951 w. s PRAEG T AL GEAR FINISHING MACHINE Filed Jan. 19, 1948 4 Sheets-Sheet 2 INVENTORS WALTER $.PRAEG BY ARTHUR B. BASSOFF ATTORNEYS g- 23, 1951 *w. s. PRAEG ET AL 2,565,883

GEAR FINISHING MACHINE WALTER $.PRAEG BY ARTHUR B. BASSOFF q 6:6 ATTORNEYS W. S. PRAEG ET AL GEAR FINISHING MACHINE 4 Sheets-Sheet 4 Filed Jan. 19, 1948 FIG 7 l/IZ S F W R F E m 0 N as m HA H mm. A $8 RW 1 EH LT AR WA Y. B W m %///////////////////////////7///////VM/M w FIG-3.

FIG-6 Patented Aug. 28, 1951 GEAR FINISHING MACHINE Walter S. Praeg. and Arthur B. Bassoif, Detroit, Mich., assignors to National Broach & Machine Company, Detroit, Mich., a corporation of Michigan 4 Application January 19, 1948, Serial No. 2,976

15 Claims.

The present invention relates to a gear finishing machine and more particularly to a multiplepurpose machine designed to carry. out a plurality of methods of gear finishing.

It is an object of the present invention to provide a gear finishing machine adapted to carry out so-called conventional gear shaving in which relative traverse'between the gear and tool is in a direction parallel to the axis of the gear but which is adjustable to provide for relative traverse in a direction which makes a substantial angle with the axis of the work gear, this angle being referred to as the traverse angle.

It is a further object of the present invention to provide a gear finishing machine of the character described with adjustable feeding means i whereby the'feeding cycle may be changed to correspond to the proper cycle for the particular type of gear finishing being carried out,

It is a further object of the present invention to provide in a gear finishing machine of the character described feeding means which are adjustable to accomplish relative infeed between the gear and tool in a plurality of steps followed by a relative outfeed in an amount equal to the sum of the separate relative infeeds.

It is a further object of the present invention to provide in a gear finishing machine of the character described feeding means for effecting relative infeed between the gear and tool of a predetermined total amount in a plurality of steps of predetermined amount.

It is a further object of the present invention to provide in a gear finishing machine of the character described cam supporting means movable in accordance with relative traverse between a gear and tool carried by the machine, in combination with removable and replaceable cams effective to vary the feeding cycle of the machine in accordance with the traverse angle.

It is a further object of the present invention to provide in a gear finishing machine of the character described feeding means operable to perform different feeding cycles which may be predetermined by the selection of suitable cams, in combination with feeding mechanism including adjustable means for predetermining the direction of feed, the amount of separate increments of infeed, the total amount of infeed, the selection of outfeed and the control of the total amount of outfeed where outfeed is selected.

It is a feature of the present invention to provide in a gear finishing machine of the character described feeding means comprising a doubleacting ratchet, an infeed pawl, an outfeed pawl and cam controlled, pawl supporting means for effecting movement of the pawls in opposite directions.

It is a further feature of the present invention to provide feedingmeans as described above in combination with means for selectively rendering said outfeed pawl inoperative.

It is a further feature of the present invention to provide feeding means as described abovepin combination with means for adjusting the amount of infeed or outfeed independently of. the movement of the pawl supporting means.

Other objects and features of the invention will become apparent as the description proceeds, especially When taken in conjunction with the accompanying drawings, wherein:

Figure 1 is a front elevation 'of'the gear finish ing machine embodying the present invention; Figure 2 is a side elevation of the machine shown in Figure 1, with parts in section;

Figure 3 is a fragmentary vertical section through the means for effecting relative. radial feed between the work gear and the tool; Figure 4 is an enlarged elevation showing the feeding mechanism; Figure 5 is a section on the Figure 4;

Figure 6 is a section on the line 6-6, Figure 4, with parts omitted;

broken line 5-5.

Figure '7 is a section on the broken line 'I-I, Figure 4; v Figure 8 is a section on the broken line 8-8, Figure 4; I v

Figure 9 is asection on the broken line 9-9, Figure 4; v I Figure 10 is a section on the line Ill-l0, Figure I Figure 11 is .a transverse section through the ratchet illustrating a. modified form of attach ing the ratchet disk to itssupporting shaft;

Figure 12 is an end elevation of the'ratcliet supporting adapter shown. in Figure 11; A Figure 13 is an end view of a substitute cam for effecting repeated infeed between the work and the cutter; and

Figure 14 is a section on the line [4-44, Figure 13.

Referring now to the drawings, the gear finishe ing machine comprises a main frame [I] having a column vll provided at its front portion with verticallyextending ways 12 on which is mounted a vertically movable knee l3. At the upper portion of the] knee are provided horizontally extending ways 14 upon which is mounted a car ijiag'e fi. ilt the upper endof thecolumnl is a forwardly projecting arm I8 which overlies the carriage [5. To the underside of the arm I8 is secured a tool supporting head 19 which is angularly adjustable about a vertical axis on suitable means, such for example as circular T-slots. The head I9 includes means for supporting a rotary tool T which may be in the form of agear shaving cutter. Means are provided for effecting positive rotation of a spindle 20 which supports the tool T.

Mounted on a trunnion 25 on the. carriage i is a rockable table 26. Means are provided for locking the rockable table in horizontal position; these means taking the form of locking pins as indicated generally at 21. However, when it is desired to effect a gear finishing operation known as gear crowning, the pins 2 1 are. released. and. the table 26 is rocked about the axis of the. trunnion support 25 through the coaction of an adjustably inclined cam guide 30 which receives a pin indicated at 31; the pin being rig-idly carried by the table 26'. The cam 30"is' supported by a bracket 32 extending upwardly from theknee I 3.

Mounted on the'upper surface of'the table 26 is a gear support 35 which is angularly adjustable about a vertical axis relative to the support, the means for efiecting this adjustment comprising any suitable means, such forexampleas the circular T-slots indicated at 36'. A scale 31' is preferably provided' which indicates the angularity at which the support 35 is set. Mounted on the upper surface of the support 35 are head and tailstocks 40 and ll, respectively, between which a work gear W to be shaved is mounted. The work gear is mounted for free rotation and is driven during operation of the machine through its'intermeshing engagement with the positively driven tool T; Inasmuch as relative traverse between the tool' T and they gear W is in the direction of'the ways I4; that is, horizontal and transversely across the front of the machine, the angular adjustability of'the support 35 and the tool supporting head f5 permits a variety of gear shaving operations to becarri edout. Until recently the majority of gearshaving operations were carried out by providing a relative reciprocation between the gear and tool in a'direction parallel to the axis'of the gear. Recently substantial unexpected advantageshave been found to reside in eiiecti'ng relative traverse between the gear and tool in a direction which occupies a plane'parall'el to the axis'of'the gear and tool but which direction is angularly related to the axis 01 the gear; The angle between the direction ofv traversev and the axis. of the gear is referred to herein as the traverse angle. Preferablythis angle is a substantial angle less than 60; It will be appreciated that since the direction of traverse of the gear is fixed,'the'traverse angle is determined bythe' angular-setting of the support 35. Since the tool support I9- is also angularly adjustable the tool T" may be meshed with the gear W at'the desired crossed axes setting irrelspective of the traverse angle-setup by appropriate adjustment of the support 35.

The present machine istherefore adapted to carry out the conventional gear shaving operation in which relative traverse is in a direction parallel to the axis of'the gear' or the newly developed method of gear shaving. known as diagonal traverse. In the conventional method of gear shaving it is normally desirable to provide for a relative reciprocation between the gear' and tool comprising a number of' traverse strokes; as for example four, six; eight or-mor: The cycle in conventional gear shaving comprises one stroke of traverse, a predetermined infeed (accomplished in this case by vertical adjustment of the knee l3) a return stroke of traverse, a second predetermined infeed, and so on until the gear has been finished to final depth. Preferably following this one or more idle strokes are taken to improve the finish. Thereafter themachine comes to rest and the knee I3 is lowered, as for example by the hand wheel 45, whose connections will be subsequently described.

However, the method of finishing gears known as diagonal traverse provides for a much more efiicient and rapid removal of stock so that it is found that the normal gear may be shaved by a single over and back reciprocation. The cycle may be variedv in diagonal traverse to include the following:

' (1) Either before or upon initiation of the first stroke of traverse the knee may be raised from a so-calledloading position to initial cutting position, which isfollowed by an over and back stroke of traverse without additional feed, and upon completion of-thi-ssecond stroke of traverse the knee I3 may beloweredto loading position.

(2-) The cycle may be as described aboveexcept that at or about completion of the first stroke of traverse a second small infeed may be provided, the amount being selected such that the first stroke of traverse is a roughing stroke and the second stroke of traverse is a finishing stroke;

3) Movement of the knee from end to loading position may be omitted so that the cycle comprises merely an-over and-back stroke of travuse without infeed.

(4-) The cycle may be as in- (3) above except that at or about completion of the firststroke of traverse a.- sma-ll amount of" i-nieed may be made so that the return strokeof traverse is a finishing stroke.

The problem is presented of providing feeding means effective tocarry out the various feeding cycles requiredfonthedifierent methods of gear finishing of which the machine is capable. It is of course desirableto provide feeding mechanism which will carry out the several feeding cycles with a minimum of adjustment and replacement of parts; According tothe present invention a cam controlled pawl and ratchet type of feed has been" adopted and inorder to change from the multiple infeed desirable With conventional gear shaving to the combined infeed and outfeed normally desirable with diagonal traverse it isnecessary onlyto remove the readily accessible cam assembly and replace it with a different cam assemb1y.

R'eferringinow-toFigure' 3, the mechanism for effecting vertical adjustment of the knee I3 is illustrated: The forwardly projecting portion of the frame. I'll carries a. feed nut 55' which is engaged:by a feed'screw'5'l carried by or formed on a vertical shaft 52* supported in the knee; weight of'theknee is taken up by a thrust bearing indicated at 53'. Attheupper endof the shaft 52 is provided a, bevel gear 54 which meshes with a bevel gear'carried' by a shaft actuated by the hand wheel 45' previously'referred to". Accordingly; rotation of the hand wheel 45 results in rotation of the shaft 52iand accordingly'results in up or down movement of the knee 13. The mechanism for'efiecting traverse of the carriage l5 comprises a'feednut tfl'depending'from theunderside of-th'eicarriage whichreceives'a feed screw 6'l'driv en by-bevef gears't'z; 63; shaft 64, bevel gears 65,

The V 66 and gears 61 and 68, the latter being connected to a motor driven shaft 69. The shaft 64 is provided with a worm I which meshes with a worm gear II carried by a shaft I2 on which is mounted cam supporting mechanism later to be described. The feeding mechanism includes the cam and pawl and ratchet mechanism connected to a second shaft 15 which carries a bevel gear I6 meshing with a second bevel gear 11 keyed or otherwise secured to the vertical feed shaft 52. Accordingly, the vertical feeding movement of the knee I3 may be effected by the hand wheel 45 or may be automatically controlled by rotation of the shaft I5, as will now be described.

The shaft I2 as outlined above will be rotated in timed relation to relative traverse of the carriage I5. Mounted on the outer end of the shaft 12 is a cam structure comprising cam plates 80, BI and 82. (See Figure 5.) These plates are held in assembled relation on the shaft I2 by a clamping disk 63 and a screw 84. Referring now to Figure 4, there is mounted adjacent the earns 80, SI and 82 a lever 88 which is pivoted on a pin 89. The lever 88 is provided with an upwardly extending arm 90 carrying an adjustable abutment 9| and a downwardly extending arm 92 having a tooth-shaped recess 93 formed therein. A second lever 95 is pivoted as indicated at 96 and has a tooth-shaped projection 91 received in the recess 93 and adapted to be moved thereby upon rocking movement of the lever 88. The lever 95 in addition is provided with a pair of tooth-shaped projections 99. The shaft I at its outer end is provided with a double-acting ratchet disk I00, the periphery of which is provided with symmetrically angled ratchet teeth IOI to provide for actuation of the ratchet disk in opposite directions, as will subsequently appear. Conveniently, the teeth IOI of the ratchet disk may be provided by forming 90 notches in the periphery thereof. Loosely mounted on an enlarged portion I05 of the shaft I5 is a pawl support I06 which is provided with an arm I01 to which is connected a relatively light tension spring I08, the opposite end of which is secured to a pin I09 carried in the knee I3. The pawl support I06 at its outer end carries a forward or infeed pawl IIO which is pivoted as by a screw H I and carries a pin II2 to which is connected a light tension spring H3. A similar but reversely positioned reverse or outfeed pawl H4 is carried by the pawl support I06, the pawl lid beingpivoted as by a screw II5 to, the pawl support I06 and carrying a pin II6 to which the opposite end of the tension spring. II3 is connected. The operating portions of the paWls i It and I I6 are shaped to enter the notches of the ratchet disk and by virtue of their support each of the pawls will operate to transmit rotation to the ratchet disk I00 in one direction only.

Associated with the ratchet disk I00 are a pair of masking or blanking plates I20 and I2I.

The arrangement of cams illustrated in Figure 4 is intended for use when the gear finishing machine is employed to practice diagonal traverse, that is, the method in which the relative traverse between the gear and tool is in a direction which makes a substantial traverse angle with the axis of the gear. The lever 88 is provided with a pair of rollers I25 and I26 which occupy spaced planes of rotation, as best illustrated in Figure 9. The roller I25 as seen in Figure 9 is substantially wider than the roller I26 and is adapted to engage camming portions formed on both of the outer cam disks BI and 82..

The inner roller I26 is relatively narrow-and is adapted to engage .camming projections formed only on the inner xcam disk 80. The parts as illustrated in Figure 4 are in initial position corresponding to the beginning of a cycle. The cams upon initiation of traverse of the carriage I5 will commence to rotate in the direction of the arrow I30. Initial rotation of the cams in the direction of the arrow I30 will cause the cam rise I3I on the cam 8I to engage the roller I25 and will accordingly rock the lever 88 in a counterclockwise direction by an amount determined by the height of the rise I3I and the position of the lever 88 prior to engagement therewith. This rocking movement of the lever 88 is transmitted with multiplied motion to the lever 95 and will rotate the lever 95 in a clockwise direction. This again is transmitted with multiplied motion to the pawl support I06 which is thereby caused to rotate in counterclockwise direction. With the masking or blanking plates I20 and I2I in the position shown, this rocking movement of the pawl support I06 will result in an identical angular movement of the ratchet disk I00. The cam BI except for the cam rise I3I and a relatively closely spaced fall portion I32 is circular so that throughout the initial stroke of traverse of the carriage I5, the roller I25 rides on the circular periphery of the cam 8I. The rotation which is thus imparted to the ratchet I00 is transmitted through the bevel gears I6 and l! and is adapted to raise the kne I3 from loading position to a predetermined initial cutting position. Initial traverse of the carriage I5 results in rotation of the cams and the cam disk 82 is secured in adjusted position such that its rise I33 engages the roller I25 substantially at the completion of the initial stroke of traverse. It will be observed that the cam rise I33 is slightly higher than the circular periphery of the cam 8| and accordingly this will impart a. slight additional rotation to the lever 88 and accordingly will result in a slight additional infeed.

between the gear and tool substantially at the: end of the first stroke of traverse. Suitable: means (not shown) are provided for effecting re-- verse traverse of the carriage I5 at this time which is accompanied by reverse rotation of the several cams. At this time since the pawls H0 and H4 together cooperate to provide a rigid interlock between the pawl supporting plate I06 and the ratchet I00, separation of the rise I33 from the roller I25 will not result in any rotation of the lever 88 even though the relatively light spring I08 is acting in a direction tending to cause the roller I25 to engage the cam. However, substantially at the completion of the second or return stroke of traverse the cam rise I34 on the cam disk engages the other roller I26. The cam 80 is positioned so that its cam rise I34 is effective to engage the roller I26 just as the roller I25 is in position to enterthe recess, defined by the rises I3I and I32 in the cam disk 8|. Accordingly, at this time the lever 88 is positively rotated in the opposite direction and by means presently to be described the amount of this return rocking of the lever 88 is equal inamount to the sum of the amounts of rotation of the lever in the opposite direction imparted thereto by cam rises I3I and I33. Therefore upon completion of the second stroke of traverse the lever 88 and accordingly the knee I3 is returned exactly to its initial loading position.

The amount of infecd which is effected upon initiation of the first traverse stroke is primarily dependent as previously described, upon the rise of the cam surface I3I.' However, the actual in-' feed resulting from the predetermined rocking movement of the lever- 88 may be controlled by suitable adjustment of the masking plate I20. Thus, for example, if the masking plate I20 is rotated in a counterclockwise direction as seen in Figure 4 so as to cover any predetermined number of notchesin the ratchet plate, initial movement of the pawl support I06 will result in the pawl I I riding on .the projecting edge of the masking plate I20, so that the. initial amount of upfeed will be that which would be produced by a predetermined movement of the lever 88 less the movement of the lever 88 during which the pawl H0 is prevented from engaging the ratchet teeth. a I

The amount of feed which takes place at or near the completion of the first traverse stroke depends upon the amount by which the camming portion I33 projects above the cylindrical periphery of cam 8I and may be varied by changing cam plates 82.

Masking plate I2I is adjusted relative to the ratchet so that the total amount of return movement of the feed mechanism is equal to the total of initial and secondary upfeed.

If it is desired to employ the machine to perform conventional gear shaving, in which case it is preferable to provide a plurality of separate upfeeds at the end oi each stroke of reciprocation and to limit thetotal amount of suchupfeed to a predetermined amount, the setup illustrated in Figures 13 and 14 is employed. In this case the downfeed or return cam 88 shown in Figure is omitted and substitutedtherefor is a spacer disk I46. Additional cam plates MI and I 42 are mounted on the shaft 12, retained in place as before by the clamping plate 83. As best seen in Figure 13, the cam'plates I M and I42 each have small cam rises I 43 and IM respectively, both of which are on a plane of rotation registering with the infeed roller I25. Cam plates MI and I42 are angularly adjusted with respect to the cycle of the-machine so that one or the other of the cam rises I'd-3 and I44 engages the roller I25 just prior to completion of a stroke of traverse in either direetiont When this apparatus is employed the downfeed or reverse pawl I I4 is swungabout its pivot point so that the pin I I5 is on the opposite side of the pivot center which retains the pawl in inoperative position. This frees the mechanism so that after each upfeed which takes place in the manner previously described, the spring I08 is eifective to return the mechanismto an initial position, which in this case is limited by engagement between the adjustable pin 9| and one of theadjustable stop surfaces I56 of an adjustment device I5I provided with a lever I52 and associated with an indicating pointer I53. It will be appreciated that under the influence of the spring, lever 88 is rotated in a clockwise direction until the ad'- justable stop 9| engages one of the stop surfaces I50. This may take place while the roller I25 is spaced from the circular periphery of the cams I4I or I42 so that the next actuation of the lever 88 by one of the cam surfaces I43 or I44 will be efiective to produce an infeed of less than the total possible amount. Thus for ex ample, the adjustable infeed setting device I5I may be graduated to produce infeeds of one; two, three or four thousandths of an inch. Blanking plate IZIY'is adjusted to interrupt feed after desireddepth reached.

tion to traverse.

In order to provide for manual raising and lowering of the knee I3 as desired, means are associated with the pawls III! and IM to render them both ineffective by operation of a single lever. As best seen in Figure 4, a lever I is pivoted as indicated at I6I and at its upper portion is provided with an elongated slot I62 which receives a pin I63 eccentrically mounted with respect to a rotary plug I64 journaled in a portion of the knee I3. The plug I64 is provided with an operating lever I65 and is adapted to be re-,= tained in one or the other of two positions of adjustment by a spring pressed ball I66 (Figure 8) engaging in one or the other of a pair of recesses I61 or I68. The lower end of the lever I66 is connected as by a pin I10 with the bottom .plate [H of a pawl disabling device which in cludes a flange I12 extending upwardly from the bottom plate I1I into the plane of the pawls III) and II 4. The bottom plate I1I is provided with an elongated opening I15 which permits longi-' tudinal sliding movement of the pawl disabling device upon manipulation of the lever I68. When the pawl disabling device is moved to the i right as seen in Figure 4 the flange I12 engages the outer ends of both of the pawls H8 and H4 and moves their pointed ratchet engaging por-= tions out of engagement with the ratchet teeth. At this time through the operation of the hand Wheel 45 the knee I3 may be raised and lowered freely.

Referring now to Figures 11 and 12, means are provided giving a micrometer adjustment as to infeed. The present type of gear finishing machine is adapted to finish gears to a very high degree of accuracy on the order of a few ten thousandths of an inch. Inasmuch as the ratchet teeth are preferably provided so that rotation of the ratchet by an increment equivalent to one of the ratchet teeth results in a relative feed of one thousand of an inch, it is neces sary in order to obtain control of the finish to small fractions of a thousandth of an inch to provide for adjustment in the mechanism. This adjustment may convenientl take the form of a serrated ratchet supporting ring I86 keyed or otherwise secured to the shaft 15 and provided with a serrated periphery as indicated at "ii in Figure 12, the number of serrations on the ring bearing a predetermined dilferential relationship to the number of serrations provided on the outer periphery of the ratchet disk I66. In this case the ratchet disk I will of course be provided with aserrated opening adapted to interfit with the serrated teeth provided on the periphery of the ring I88. By this means any desired fineness of control in the final position of the knee l3 may be obtained.

The gear finishing machine of the present il1-' vention is particularly Well adapted to carry out an operation known as gear crowning employing diagonal traverse. Inasmuch as diagonal traver'se as described above may result in causing the finishing action of the tool to move completely across the face of the gear as a result of a rela-' tively short traverse stroke, it is often necessary to provide special means for moving the gear and tool away from each other at the completion of a; crowning stroke oftraverse.

As described above, the crowning operation is carried out by rocking the table 26 through the agency of cam means 30 and 3| in timed rela--- The rocking is carried out in such a manner that as the zone of action moveslongitudinally of a gear tooth from one end thereof to the other, the portion adjacent the end of the gear tooth which is being operated upon is moved radially inwardly with respect to the teeth of the cutter so as to remove more material from adjacent the end of the gear teeth than from the central portion thereof. The camming mechanism disclosed herein will normally provide for continued rocking so long as traverse takes place, with the result that the gear and tool may remain in tight mesh at the end of a stroke instead of moving into clearance, as would be the case were the crowning motion omitted.

Since the present invention provides automatic means operable in accordance with translation for effecting relative infeed and relative outfeed between the gear and tool, it is possible to provide a finishing cycle which comprises first relative infeed between the gear and tool from a separated loading position to an initial cutting position, followed by two or more strokes of traverse, either with or without additional infeed as desired, and terminating in a final stroke of traverse, accompanied by the rocking motion to produce the crowned formation, upon the completion of which a relative outieed takes place between the gear and tool, thus moving the gear and tool supports into position to receive a new work gear prior to initiation of a second cycle.

As outlined above, the combination of con trolled in and out feed for the purpose set forth is peculiarly well adapted to the method of crown finishing gear teeth by diagonal traverse. Normally where the crowning motion is carried out in conjunction with a relative traverse in a direction parallel to the axis of the gear, it is not necessary to provide for relative outfeed upon the termination of the finishing cycle, although such may of course be provided if desired.

The drawings and the foregoing specification constitute a description of the improved gear finishing machine in such full, clear, concise and exact terms as to enable any person skilled in the art to practice the invention, the scope of which is indicated by the appended claims.

What we claim as our invention is:

'1. A gear finis ing machine comprising a frame. an an ularly adiustable tool support on said frame. an angularly adiustable work support on said frame, ways on said frame in which one of said su ports in slidable, rotarv spindles carried by said su orts adapted to carry an intermes ing ear-li e tool and work' gear with their axes crossed, means for rotatin one of said spindles. means for traversing said one support back and forth on said wa s, means for efiecting relative depth feed between said spindles comprising cam means for relatively movin said spindles from loading position to initial cutting position, and additional cam means operable at the end of the first stroke of traverse to provide an additional depth feed, said cam means being effective upon completion of the second traverse stroke to relatively move said spindles to loading position.

2. In a gear finishing machine, a rotary work gear support, a rotary tool support, one of said supports being movable in a direction generally radial of the work-gear and tool, one of said supports being movable back and forth in traverse in a plane parallel to the axes of both said supports, and means for controlling the said radial movement of the support comprising relatively rotatable feed screw and nut elements, a ratchet for rotating one of said elements, a double-act ing pawl device having a pair of spring-pressed pawls and a rocker arm carrying said pawls, a lever for moving said rocker arm, a first cam for moving said lever upon initiation of traverse to effect substantial rotation of said ratchet to move said support from loading to initial cutting position, a second cam for moving said lever in the same direction to effect a depth feed at the end of the first stroke of traverse, and a third cam operable at the end of the return stroke of traverse to move said lever in the opposite direction to move said support to loading position.

3. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for eiiecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for effecting relative radial feed between said supports, said last named means comprising cam and ratchet means for effecting a first relative infeed upon initiation of traverse, and adjustable masking means for the ratchet means for varying the amount of said first infeed, said cam and ratchet means comprising a member effective to provide a second relative infeed upon completion of the first stroke of reciprocation, said cam and ratchet means comprising a second member efiective to cause relative outfeed between said supports.

4. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for efiecting relative radial feed between said supports, said last named means comprising cam and ratchet means for effecting a first relative infeed upon initiation, of traverse, and adjustable masking means for the ratchet means for varying the amount of said first infeed, said cam and ratchet means comprising a member effective to provide a second relative infeed upon completion of the first stroke of reciprocation, said cam and ratchet means comprising a second member effective to cause relative outfeed between said supports, said last member having means cooperating therewith to control the amount of outfeed to provide for an amount of outfeed equal to the sum of the amounts of said first and second infeeds.

5. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for effecting relative radial feed between said supports, said last named means comprising a double-acting ratchet, a rockable pawl support, means rocking said pawl support in opposite directions upon traverse of said carriage in opposite directions, an infeed pawl and an diseases pawls ineffective.

-6. A multiple-purpose gear shaving machine comprisinga frame, a carriage slidable on said base, a first rotary support on said table, means 1 for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means 'ior' driving one of said rotary supports, adjustable means for effecting relative radial feed between said supports, said last named means comprising adouble-acting ratchet, a rockable pawl support, 'means rocking said pawl support in opposite directions upon traverse of said carriage in opposite directions, an infeed pawl and an oppositely directed outfeed pawl in said pawl support, and masking means associated with each of said pawls to vary the amount of infeed and outfeed.

7. A multiple-purpose gear shaving machine comprising a frame, .a carriage slidable on said base, a first rotary support on said table, means for efiecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for [driving one of said rotary supports, adjustable means for eifecting relative radial feed between said supports, said last named means comprising a double-acting ratchet, a rockable pawl support, means rocking said pawl support in opposite directions upon traverse of said carriage in opposite directions, an infeed pawl and an oppositely directed outffeed pawl on said pawl support, means for selectively rendering said pawls ineffective, and a set of removable cam elements for efiecting different cycles of feed cooperating with said pawl "support.

8, A multiple-purpose gear shaving machine comprisin a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for efiecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for effecting relative radial feed between said supports, said last named means comprising a double-acting ratchet, a rockable pawl support, means rocking said pawl support in opposite .direc-tions upon traverse of said carriage in opposite directions, an infeed pawl and an oppositely directed outfeed pawl on said pawl support. means for selectively rendering said pawls inefiective, a .set of removable cam elements for efiectin different cycles of feed cooperating with said pawl support, and means. for rendering said outfeed pawl inoperative.

9. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for effecting relative radial feed between said supports, said last named means comprising a double-acting ratchet, a rockable pawl support, means rocking said pawl support in opposite directions upon traverse of said carriage in opposite directions, an infeed pawl and an oppositely directed outfeed' pawl on said pawl support, 'means for selectively rendering said pawls ineffective, a set of removable cam elements for effecting different cycles of feed cooperating with said pawl support, means for rendering said out feed pawl inoperative, and adjustable masking means for predetermining the total amount of infeed and for terminating further infeed thereafter.

10. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on'said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for effecting relative radial 'feed'between said supports, said last named means comprising a double-acting ratchet, a rockable pawl support, means rocking said pawl support in opposite directions upon traverse of said carriage in opposite directions; an infeed pawl and an oppositely directed outfeed pawl on said pawl support, and means for rendering both of said pawls ineffective to permit manual feed.

11. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, adjustable means for effectin relative radial feed between said supportsfsaid last named means comprising a double-acting ratchet, a rockable pawl support, means rocking said pawl support in opposite directions upon traverse of said carriage in opposite directions, an infeed pawl and an oppositely directed outf-eed pawl on said pawl support, means for selectivelyrendering said pawls ineffective, 'a set of removable cam elements for effecting different cycles'of feed cooperating with said pawl support, means for rendering said outfeed pawl inoperative, and an adjustable member for controlling the amount of infeed resulting from each rocking movement of said pawl support.

'12. A gear finishing machine comprising angularly adjustable work and tool supports for supporting a gear and tool in mesh at crossed axes, means for rotating one of said supports, means for effecting relative traverse between said supports in a direction which occupies a plane generally parallel to the axes of the gear and tool which direction may be parallel to the axis of said gear or oblique thereto, feeding means operable in accordance with traverse and adjustable to conform the relative feed to the traverse angle between the direction of traverse and the axis of the ear, said feeding means comprising a cam support for supporting cams selected in accordance with the trave'r se angle, and selectively operable 'in'eans fog-effecting relative infeed and outfeed between said gear and tool.

13. A multiple-purpose gear shaving 'machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said'frame, means for reciprocating said carriage, means for driving one of said rotary supports, selectively operable means for effecting different feeding cycles comprising a cam support rotatable in accordance with reciprocation and adapted to support cams selected in accordance with the desired feeding cycle, and reversely operable pawl and ratchet mechanism operable by cams carried by said cam support, said mechanism being selectively operable to provide for repeated infeeds without subsequent infeed, or to provide for infeed in one or more steps followed by outfeed equal in amount to the total infeed.

14. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for efiecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports. selectively operable means for effecting different feeding cycles comprising a cam support rotatable in accordance with reciprocation and adapted to support cams selected in accordance with the desired feeding cycle, and reversely operable pawl and ratchet mechanism operable by cams carried by said cam support, said mechanism comprising a for-1 ward and reverse pawl operable respectively to effect infeed and outfeed, said outfeed pawl being selectively disengageable from the ratchet to cause said mechanism to effect repeated infeed without subsequent outfeed.

15. A multiple-purpose gear shaving machine comprising a frame, a carriage slidable on said base, a first rotary support on said table, means for effecting angular adjustment of said support on said carriage, a second rotary support on said frame, means for effecting angular adjustment of said second support on said frame, means for reciprocating said carriage, means for driving one of said rotary supports, selectively operable means for effecting different feeding cycles comprising a cam support rotatable in accordance with reciprocation and adapted to support cams selected in accordance with the desired feeding cycle, reversely operable pawl and ratchet mechanism operable by cams carried by said cam support, said mechanism comprising a forward and reverse pawl operable respectively to effect infeed and outfeed, said outfeed pawl being selectively disengageable from the ratchet to cause said mechanism to effect repeated infeed without subsequent outfeed, and adjustable blanking means associated with said ratchet to interrupt further infeed at a predetermined depth.

WALTER S. PRAEG. ARTHUR B. BASSOFF.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 294,739 Lehr et al. Mar. 4, 1884 1,454,398 M-acKenzie May 8, 1923 2,347,997 Drummond May 2, 1944 2,350,882 Drummond June 6, 1944 2,435,405 Praeg Feb. 3, 1948 FOREIGN PATENTS Number Country Date 480,247 Great Britain Feb. 14, 1938 

